This invention relates to a method for recording/reproducing digital signals and, more particularly, to a method for recording/reproducing digital signals, in which multiple tracks are formed by stationary heads.
As a method for recording digital signals, such as pulse code modulated (PCM) audio signals, there is known a multiple track recording method in which digital signals of one or more channels are recorded by a stationary head so as to be distributed to plural tracks formed along the longitudinal direction of magnetic tape.
As shown for example in the Japanese Patent Publication KOKAI NOS. 104714/1984 or 145768/1986, assigned to the present Assignee, PCM audio signals, obtained by quantization into 16 bits at a sampling frequency of 32 kHz, 44.1 kHz, 48 kHz or 50.4 kHz, are selectively recorded on required ones of, for example, 8 to 48 tracks on the tape as a function of the number of channels or tape running speeds.
In a recording apparatus for these PCM audio signals, there is a demand for an increased dynamic range of the audio signals or an increased performance in data processing. For example, it is desired to enhance the word length of the recording data, so as to expand the number of quantization bits from 16 to 20 bits or record auxiliary data other than the PCM audio signals.
However, an increase in the number of bits of the words recorded in pre-existing formats for expanding the word length of the data means an increase in the recording density resulting in the necessity of elevating the tape running speed and completely modifying the pre-existing data processing system. The recording/reproducing apparatus having the format modified in this manner is disadvantageous in that it is unable to reproduce tapes recorded in accordance with the pre-existing formats, and in that, conversely, a tape recorded in accordance with the modified format is unable to be reproduced by the conventional reproducing apparatus.